Friction reducing in flowing hydrocarbon fluids

ABSTRACT

WHERE &#39;&#39;&#39;&#39;R1&#39;&#39;&#39;&#39; is H or CH3 and &#39;&#39;&#39;&#39;R2&#39;&#39;&#39;&#39; is an alkyl group of eight to 18 carbon atoms, a glycol and water. The method comprises mixing the emulsion with the hydrocarbon fluid and then adding a lower alkyl alcohol which causes the polymer to be transferred from the emulsion phase to a hydrocarbon solution.   This disclosure is directed to a method and composition useful in reducing the friction loss in flowing hydrocarbon fluids. The composition is an emulsion consisting essentially of a homopolymer or copolymer of

United States Patent Slagel et al. [451 Apr. 11, 1972 541 FRICTIONREDUCING IN FLOWING 3,537,525 11/1970 Sarem ..l66/308 HYDROCARBON FLUIDS3,542,044 11/1970 Hansen et al. ..137/13 [72] Inventors: Robert ClaytonSlagel, Pittsburgh; Arnold primary Examine, stephen Novosad EugeneBloomquwt, Bethel Park, both of Attorney-William 1.. Krayer and HerbertJ. Zeh, Jr.

a. [73] Assignee: Calgon Corporation, Pittsburgh, Pa. [57] ABSTRACT 22 1d: A 6 1 7 This disclosure is directed to a method and compositionuseful 1 Fl e ug 9 0 in reducing the friction loss in flowinghydrocarbon fluids. The PP 61,852 composition is an emulsion consistingessentially of a homopolymer or copolymer of [52] US. Cl. ..l66/308,137/13, 252/855 R,

252/85 E, 260/29.6 ME, 260/33.4 R, 260/33.6 R R1 [51] Int.Cl........Cl0m 7/26, E21b 43/26,F17d 1/16 7 l [58] Field of Search ..166/308;137/13; 252/855 R,

252/85 C, 8.5 E, 56 R; 260/29.6 R, 33.4 R, 33.6 R,

29.6 ME I [56] References Cited UNITED STATES PATENTS where R, is H orCH; and Rf is an alkyl group of 8 to 2,407,954 9/1946 Fenske et al...252/56 R 18 carbon atoms, a glycol and water The method comprises2,411,150 11/1946 Evan? et mixing the emulsion with the hydrocarbonfluid and then 2,604,453 7/1952 PORkm "252/56 R adding a lower alkylalcohol which causes the polymer to be 3215J54 1 H1965 whne ct R Xtransferred from the emulsion phase to a hydrocarbon 3,254,719 6/1966Root ..252/8.55 R Solution. v 3,451,480 6/1969 Zeh, Jr. et al ..l66/3083,493,000 2/1970 Canevari et a1 ..l37/13 12 Claims, No Drawings FRICTIONREDUCING IN FLOWING HYDROCARBON FLUIDS BACKGROUND OF THE INVENTION Thisinvention relates to reducing friction loss in flowing hydrocarbonfluids. More particularly, it relates to a method for reducing thefriction loss of hydrocarbon fluids flowing in a conduit by adding tothe hydrocarbon fluid a friction reducing additive comprising anemulsion of a polymer of where R," is H or CH and R is an alkyl group ofeight to 18 carbon atoms, a glycol and water.

In the process of transferring liquids in conduits, the problem of highfriction loss caused by nonlaminar flow is often encountered. Thisfrictional loss is especially great when the fluid is pumped under highpressures and at high velocities. In order to compensate for thisfriction loss, a considerable amount of energy must be expended inmoving the fluids.

The two most common industrial operations in which friction loss is amajor problem are oil well fracturing and the transmission of oil forconsiderable distances in petroleum pipelines. It is obvious that areduction in friction loss would permit lower surface operatingpressures, reduced power requirements and greater pressure at the bottomof the well bore in a fracturing operation and also increased flow ratesand reduced power requirements in the transmission process. Thus, it canreadily be seen that the reduction of friction in flowing hydrocarbonsfluids is greatly desired.

In the past, various materials have been proposed and used as frictionreducers in hydrocarbon fluids. For example, see U.S. Pat. No. 3,288,577which discloses the use of certain high molecular weight polymers asfriction reducers. See also U.S. Pat. No. 3,351,079 which discloses theuse of ethylene propylene copolymers and U.S. Pat. No. 3,215,154 whichdiscloses the use of polyisobutylene. Finally, see U.S. Pat. No.3,493,000 which discloses the use of polydimethylsiloxane as a frictionreducer in hydrocarbon fluids.

Recently, it has been found that certain polyacrylates and methacrylatesare excellent friction reducers in hydrocarbon fluids. However, thesolubility rate of these polymers in crude oil is slow and in order touse the polymer readily, it must be predissolved in oil, kerosene or thelike. In addition, the polymers are usually prepared as aqueousemulsions and it has heretofore been necessary to recover the polymersfrom the emulsions before adding them to the oil or kerosene. Theseadditional steps of recovering the polymer and dissolving it increasethe cost of using the polymer. It would therefore be desirous to be ableto use the polyacrylate and polymethacrylate emulsions directly withouthaving to recover them and then dissolve them. However, the aqueousemulsions of the polymers do not have temperature stability at the lowtemperatures which are often encountered in the oil field processesespecially those temperatures encountered in the winter months in Alaskaand other areas. Therefore, even if the emulsion can be used directly,it is desirous that it have temperature stability.

SUMMARY OF THE INVENTION where R," is H or CH;, and R is an alkyl groupof eight to 18 carbon atoms, (b) from 10 to 50 percent by weight glycol,(c) from 10 to 60 percent by weight water, and (d) from I to 10 percentby weight emulsifying agent (surfactant). The preferred emulsion of ourinvention comprises (a) from 25 to 50 percent by weight of a polymer ofR where R, is H or CH; and R is an alkyl group of eight to 18 carbonatoms, (b) from 15 to 40 percent by weight glycol, (c) from 20 to 50percent by weight water, and (d) from 1 to 5 percent by weightemulsifying agent.

The useful glycols of our invention include ethylene glycol, propyleneglycol, diethylene glycol and the like. The preferred glycol is ethyleneglycol.

The polymer may be a homopolymer of the acrylate or methacrylate or itmay be a copolymer of the acrylate or methacrylate and up to 10 percentby weight of one or more suitable comonomers. Some of the suitablecomonomers are the lower alkyl acrylates and methacrylates such asmethylmethacrylate, ethyl acrylate, butyl acrylate and the like. Othersuitable comonomers include the dialkyl diallyl ammonium chlorides suchas dimethyl diallyl ammonium chloride, acrylamide and the N-substitutedacrylamides such as diacetone acrylamide. The comonomer is used toimpart various desirable properties to the final polymer. For example,the use of dimethyl diallyl ammonium chloride as the comonomer imparts aslight cationic charge to the final polymer and the use of acrylamidesprovide sites for hydrogen bonding, either of which gives the polymer ahydrophilic property. This property is desirable since the presence ofhydrophilic sites on the polymer will enhance the performance of thepolymer in hydrocarbon fluids containing small amounts of polarmaterials such as water, alcohols, thiols and the like.

The preferred polymer of our invention is polyisodecylmethacrylate.Therefore, when using the preferred polymer, the emulsion of ourinvention comprises (a) from 20 to about 60 percent by weightpolyisodecylmethacrylate, (b) from 10 to 50 percent by weight glycol,(c) from 10 to 60 percent by weight water, and (d) from 1 to 10 percentby weight emulsifying agent (surfactant). Similarly, the preferredemulsion of our invention comprises (a) from 25 to 50 percent by weightpolyisodecylmethacrylate, (b) from 15 to 40 percent by weight glycol,(c) from 20 to 50 percent by weight water, and (d) from 1 to 5 percentby weight emulsifying agent.

The emulsion of our invention may be prepared by polymerizing theacrylate or methacrylate monomer in an aqueous emulsion and then addingthe glycol or the emulsion may be prepared by polymerizing the acrylateor methacrylate in a cosolvent system of the glycol and water. The useof the cosolvent system is the preferred method. The use of thecosolvent system lowers the raw material cost, increases the yield ofpolymer and, in general, facilitates the polymerization process. Inaddition, we have found that by emulsion polymerizing the monomer in thecosolvent system of water and glycol the resulting polymer gives betterfriction reduction than a polymer prepared via an aqueous emulsion.

As mentioned above, the polymer of our invention is prepared by anemulsion polymerization technique. In the emulsion polymerization, thewater-insoluble monomer is emulsified in water/glycol cosolvent systemby means of a surfactant. A polymerization initiator is added and thepolymer is formed. The polymeric emulsion must then remain in ahomogenous state. There must be no evidence of a phase separation evenwhen subjected to freeze-thaw temperature cycles ranging from about 30F. to about F. The polymeric emulsions of our invention have thesedesired properties.

When polymerizing the acrylates and methacrylates of our invention inthe cosolvent system or in plain water, it is possible to use eithercationic, nonionic, anionic or amphoteric surfactants or a combinationof different surfactants. We have made emulsions using all types ofsurfactants. However, we have found that anionic surfactants such asdioctyl sodium sulfosuccinate give the most stable emulsions, which arenearly free from coagulum. We have also found that many differentpolymerization initiators may be used in preparing the emulsions of ourinvention. Examples of some of the useful initiators are ammoniumpersulfate, potassium persulfate, azobisisobutyronitrile, tertiary butylperoxypivalate, tertiary butyperoxide, benzoyl peroxide and the like.The preferred initiator of our invention is potassium persulfate.

The following examples illustrate the preparation and composition of theemulsions of our invention.

EXAMPLE 1 Into a one liter, four-necked flask equipped with stirrer,thermometer, reflux condenser and gas inlet tube was charged 200.0 gramsof isodecylmethacrylate, 162.0 grams of ethylene glycol and 162.0 gramsof water. The reaction mixture was purged with nitrogen for one andone-half hours. Then 16.8 grams of TRITON GR- (dioctyl sodiumsulfosuccinate) was added to the mixture. The temperature was increasedto 60 C and 0.06 grams of potassium persulfate was added. The reactionmixture exothermed to 70 C over a period of twenty minutes. The reactionwas then allowed to proceed for three hours at a temperature between 60and 70 C. The emulsion was placed in an atmosphere controlled at 30 Ffor twentyfour hours. It was then allowed to stand at room temperature70 F) for twenty-four hours. This cycle was repeated three times. Theemulsion remained as a liquid with no phase separation nor formation ofcoagulum. This emulsion gave 64 percent friction reduction in ahydrocarbon fluid as compared to polyisobutylene which gave about 36percent.

EXAMPLE 2 Into a one liter, four-necked flask equipped with stirrer,thermometer, reflux condenser and gas inlet tube was charged 200.0 gramsof tridecylmethacrylate, 162.0 grams of ethylene glycol and 162.0 gramsof water. The reaction mixture was purged with nitrogen for one andone-half hours. Then 16.8 grams of TRITON GR-5 (dioctyl sodiumsulfosuccinate) was added to the mixture. The temperature was increasedto 60 C and 0.06 grams of potassium persulfate was added. The reactionmixture exothermed to 70 C over a period of twenty minutes. The reactionwas then allowed to proceed for three hours at a temperature between 60and 70 C. The emulsion was placed in an atmosphere controlled at --30 Ffor twentyfour hours. It was then allowed to stand at room temperature70 F) for twenty-four hours. This cycle was repeated three times. Theemulsion remained as a liquid with no phase separation nor formation ofcoagulum. This emulsion showed friction reduction properties of the sameorder of magnitude as polyisobutylene when tested in a hydrocarbonfluid.

EXAMPLE 3 Into a 250 ml., four-necked flask equipped with a stirrer,thermometer, reflux condenser and gas inlet tube was charged 50 grams ofisodecylmethacrylate, 100 grams'of water, and 2.5 grams of surfactant(sodiumlauryl sulfate). The reaction mixture was then purged for onehour with argon. The temperature was increased to 60 C and 0.015 gramsof potassium persulfate was added. The reaction was then allowed toproceed for three hours act a temperature between 60 and 70 C. Thereaction mixture was cooled to room temperature and ethylene glycoladded so that the resulting mixture was 28.6 percent by weight ethyleneglycol. The emulsion was then placed in a freezer at -5 C for sixteenhours. The emulsion remained as a liquid with no phase separation norformation of coagulum. This emulsion gave 60 percent friction reduction.

EXAMPLE 4 Into a 250 ml. flask equipped with a stirrer, thermometer,reflux condenser and gas inlet tube was charged 40 gramsisodecylmethacrylate, 22 grams ethylene glycol, 38 grams water and 2grams sodium lauryl sulfate. The reaction mixture was then purged forone hour with argon and heated to 60 C. Then 0.012 grams potassiumpersulfate was added and the reaction allowed to proceed for three hoursat a temperature between 60 and 70 C. The emulsion was then subject to afreeze-thaw cycle ranging from -20 C to room temperature. The emulsionwas stable with no phase separationnor coagulum. This emulsion gave 59percent friction reduction.

EXAMPLE 5 Into a 250 ml., four-necked flask equipped with a stirrer,thermometer, reflux condenser and gas inlet tube was charged 50 grams ofisodecylmethacrylate, 33 grams of ethylene glycol, 30 grams water and2.5 grams TRITON GR-S. The reaction mixture was purged for one hour withnitrogen and heated to 60 C. Then 0.015 grams of potassium persulfatewas added and the reaction allowed to proceed for three hours at 60 to70 C. The resulting emulsion was stable and had no coagulum. Theemulsion gave a friction reduction of 60.4 percent and was stable totemperature below 16 C.

EXAMPLE 6 Into a 250 ml., four-necked flask equipped with a stirrer,thermometer, reflux condenser and gas inlet tube was charged 50 gramsisodecylmethacrylate, 41 grams ethylene glycol, 62 grams water and 2.5grams TRITON GR-S. The reaction mixture was purged for one hour withnitrogen and heated to 60 C. Then 0.015 grams of potassium persulfatewas added and the reaction allowed to proceed for three hours at 60 to70 C. The resulting emulsion was stable and had no coagulum. Theemulsion gave a friction reduction of 55.5 percent and was stable totemperatures below 9 F.

EXAMPLE 7 Into a 250 ml., four-necked flask equipped with a stirrer,thermometer, reflux condenser and gas inlet tube was charged 50 gramsisodecylmethacrylate, 56.5 grams ethylene glycol, 46.5 grams water and2.5 grams TRITON GR-S. The reaction mixture was purged for one hour withnitrogen and heated to 60 C. Then 0.015 grams potassium persulfate wasadded and the reaction allowed to proceed for three hours at 60 to 70 C.The result was a stable emulsion which had a small amount of coagulum.This emulsion was stable at temperatures below 43 F.

EXAMPLE 8 Into a one liter, four-necked flask equipped with a stirrer,thermometer, reflux condenser and gas inlet tube was charged 200 gramsof isodecylmethacrylate, 162 grams ethylene glycol, 162 grams water and10 grams of TRITON GR-S. The reaction mixture was purged for one hourwith nitrogen and heated to 60 C. Then 0.06 grams of potassiumpersulfate was added and the reaction allowed to proceed for threehours. The resulting emulsion was stable and had no coagulum. Theemulsion was then subjected to three twenty-four hour freezethaw cyclesranging from 30 to +70 F. The emulsion remained stable during thesefreeze-thaw cycles and gave a friction reduction of 65 percent.

EXAMPLE 9 Into a large reactor fitted with a stirrer, thermometer,reflux condenser and a gas inlet tube was charged 70.35 pounds ofisodecylmethacrylate, 56.27 pounds ethylene glycol, 56.27 poundsdistilled water and 0.018 pounds of sodium ethylene diamine tetraaceticacid. The reaction mixture was purged with nitrogen for one and one-halfhours and heated to 60 C. Then 0.018 pounds of potassium persulfate wasadded and the reaction allowed to proceed for five hours at atemperature between 60 and 70 C. The result was a stable emulsion withno coagulum. The emulsion gave a friction reduction of 65 percent.

EXAMPLE Into a one liter, four-necked flask equipped with a stirrer,thermometer, reflux condenser and gas inlet tube was charged 190 gramsof isodecylmethacrylate, 10 grams of dimethyl diallyl ammonium chloride,2.5 grams of TRITON X-305 (a nonionic surfactant), 7.5 grams of ALACSAN(a cationic surfactant), and 465 grams of water. The reaction mixturewas then purged with nitrogen for one and one-half hours and thetemperature raised to 60 C. Then 0.06 grams of potassium persulfate wasadded and the polymerization allowed to proceed for three hours at atemperature of about 75 C. The reaction mixture was then cooled to roomtemperature and the ethylene glycol was added so that the resultingpolymer emulsion was about percent by weight glycol. This emulsion wasthen subject to a freeze-thaw test. The test was three cycles rangingfrom a temperature of 30 F to +70 F. The emulsion was very stable andthere was no phase separation at the end of the freeze-thaw test. Thisemulsion gave a friction reduction of 69 percent as compared to 36percent for polyisobutylene and 64 percent forpolyisode'cylmethacrylate.

EXAMPLE 1 1 into a one liter, four-necked flask equipped with a stirrer,thermometer, reflux condenser, and gas inlet tube was charged 190 gramsof isodecylmethacrylate, 10 grams of diacetone acrylamide, 10 grams ofsodium lauryl sulfate, and 440 grams of water. The reaction mixture wasthen purged with nitrogen for one and one-half hours and the temperatureraised to 60 C. Then 0.06 grams of potassium persulfate was added andthe polymerization allowed to proceed for three hours at 75 C. Thereaction mixture was then cooled to room temperature and ethylene glycolwas added so that the emulsion was about 30 percent by weight ethyleneglycol. This emulsion was stable after a three cycle freeze-thaw testhaving temperatures ranging from +30 F to +70 F. This emulsion gave 64percent friction reduction.

In addition to the isodecylmethacrylate emulsions illustrated above, wehave also prepared emulsions of other acrylates and methacrylates in amanner similar to those described in Examples 1 to 11 above. Among thedifferent acrylates and methacrylates which have been found to be usefulin our invention and which we have used to prepare emulsions are: 2ethylhexyl acrylate, tridecyl methacrylate, laurylacrylate,1aurylmethacrylate, stearyl acrylate and stearyl methacrylate. The emulsionsof these compounds all give a friction reducing effect in hydrocarbonfluids.

The friction reduction properties of the emulsion of our invention weredetermined in a hydrocarbon fluid which was pumped from a containerthrough a standard section of pipe and back into the container. Thistype of equipment is called a friction loop. The pressure drop in thepipe is continually measured and recorded. The pressure drop refers tothe loss or drop in pressure due to the friction of the fluid flowingthrough a conduit at a given velocity. The loss is measured by thedifference in pressure between any two given points along the conduitdivided by the distance between the two points. The friction reductionis a measure in the change in pressure drop due to the use of anadditive. It is the decrease in the pressure differential required tomove the same fluid through the same distance of the same pipe at thesame velocity. The percent friction reduction is expressed by theformula where A Pu is the pressure drop per unit length of pipe causedby the friction of the untreated base fluid and where A Pa" is thepressure drop per unit length of pipe caused by the friction of the basefluid with additive. Thus, the higher the number, the more effective thefriction reducing characteristics of the emulsion.

There is no reason to believe that there is a minimum molecular weightwhich must be achieved by the polymer in order to show friction reducingproperties. A low molecular weight polymer will have a slight effectwhen compared to a high molecular weight polymer. However, for allpractical purposes, it may be said that the polymer should have amolecular weight of at least 1,000,000. Similarly, there is no reason tobelieve that there is a minimum quantity which must be used to achieve afriction reducing effect. A small amount will have a slight effect. Butfor practical purposes a minimum of 50 ppm based on total weight ofhydrocarbon fluid is necessary. The maximum amount used will'largely be'determined by economic considerations. However, concentrations greaterthan 1,000 ppm will seldom, if ever, be used. In the majority of cases,a concentration in the neighborhood of 200 to 500 ppm will produce acommercially significant effect. The friction reduction values for theemulsions of our invention given in the examples were determined at aconcentration of 400 ppm based on active polymer and total weight ofhydrocarbon fluid, which was kerosene.

We have also found an effective method of using the emulsions of ourinvention in hydrocarbon liquids without having to first isolate thepolymer from the emulsion. Our method comprises adding the emulsion andhydrocarbon fluid together then adding to this mixture an alcohol suchas isopropanol or methanol. The alcohol causes the polymer to betransferred from the aqueous phase to the hydrocarbon phase. Theemulsion may be an aqueous emulsion of polymer and water or it may be anemulsion of polymer in the water/glycol cosolvent system. Our method canalso be practiced by adding the polymer emulsion and ahydrocarbon/alcohol mixture together. In addition, our method may bepracticed by simultaneously adding together the polymer emulsion, thehydrocarbon fluid, and the alcohol. In practicing any one of the abovevariations of our method, it must be remembered that the time of addingthe alcohol is critical. The alcohol should not be added to the emulsionprior to the time when the emulsion and hydrocarbon fluid are mixed. Wehave also found that the weight ratio of alcohol to polymer is acritical factor in using the method of our invention. When adding thepolymer emulsion and hydrocarbon fluid together, it is necessary to keepthe ratio of alcohol to emulsion between 1:2 and 5:1. The ratio ofalcohol to emulsion determines the speed and efficiency of the transferof the polymer from the emulsions to the hydrocarbon fluid. The maximumratio may be increased to values greater than 5:1 without having anydeleterious effect on the invention. However, we have found that for allpractical purposes, no advantage is gained by using a higher ratio.Similarly, amounts smaller than the minimum ratio of 1:2 may be used.However, we have found that when these small amounts are used thetransfer process is slow and inefficient. The preferred ratio of thealcohol to emulsion is from 1:1 to 4:1. The alcohols which may be usedin practicing our invention may be described as lower alkyl alcohols;that is, alkyl groups of from about one to six carbon atoms. Someexamples of these alcohols are methanol, ethanol, propanol, butanol,pentanol, hexanol, isopropanol, isobutanol, tertiary butanol, and thelike. The preferred alcohols are methanol and isopropanol. We have alsofound that acetone may be used in place of the alcohol and the termlower alkyl alcohol as used herein includes acetone unless otherwisestated.

The ratio of emulsion to hydrocarbon fluid will depend upon the amountof polymer that is desired in the hydrocarbon fluid and theconcentration of polymer in the emulsion. For example, if it is desiredto have the hydrocarbon fluid contain 0.5 percent by weight polymer andthe emulsion contains 20 percent by weight polymer, then the weightratio of emulsion to hydrocarbon fluid would be 2.5:99.5. Similarly, ifit is desirous to have a hydrocarbon fluid containing 10 percent byweight polymer and the emulsion is 40 percent by weight polymer, thenthe weight of emulsion to hydrocarbon fluid would be 25:90. Finally, forexample, if it is desirous to have a hydrocarbon fluid containing 10percent by weight polymer and the emulsion contains 20 percent by weightpolymer, then the ratio of emulsion to hydrocarbon fluid would be 50:90.

The following examples illustrate the method of our inventron.

EXAMPLE l2 Into one holding container was placed 100 grams of a 33percent by weight polyisodecylmethacrylate emulsion (100 ml.). lntoanother holding container was placed 383 gramsof kerosene (480 ml.) and67 grams of isopropanol (86 ml. The solutions were pumped from theholding container at a ratio of 5.6 ml. of the kerosene/isopropanolmixture to 1 ml. of the emulsion into a static mixer such as describedin US. Pat. Nos. 2,894,732; 3,051,452; 3,051,453; 3,182,965; 3,195,865;3,206,170. As the mixture passed through the static mixture thepolyisodecylmethacrylate was transferred from the aqueous phase to thekerosene. The kerosene effluent was a very viscous solution containingabout 8 percent by weight polyisodecylmethacrylate.

EXAMPLE 13 Using the procedure described in Example 3, an emulsion wasprepared comprising 400 grams of polyisodecylmethacrylate, 800 gramswater and 20 grams of sodium lauryl sulfate. Then 14.4 parts of theemulsion was placed in 250 parts of kerosene and 25 parts of isopropanolwas added. This mixture was stirred for several minutes with amechanical agitator. The polyisodecylmethacrylate was transferred fromthe aqueous phase to the kerosene and the result was a viscous kerosenesolution containing 0.2 percent by weight polymer.

EXAMPLE 14 An emulsion comprising 33 percent by weightpolyisodecylmethacrylate in the cosolvent of ethylene glycol and waterwas prepared in a manner similar to the one described in Example 1. Then9 parts of the emulsion were added to 250 parts of kerosene and then 20parts of isopropanol were added to the mixture. The mixture was stirredfor several minutes and the polyisodecylmethacrylate was transferredinto the kerosene. The result was a kerosene solution containing 0.12percent by weight polymer.

EXAMPLE 15 fluid prior to injection with an aqueous polymer emulsioncomprising (a) from to 60 percent by weight of a polymer 8 where R isHot CH and R is an alkyl group of eight to 18 carbon atoms, (b) from 10to 50 percent by weight glycol (c) from 10 to 60 percent by weightwater,and (d) rom l to 10 percent by weight surfactant, said polymer emulsionbeing added in an amount such that the treated hydrocarbon fluidcontains from about 50 ppm. to 1,000 ppm. of

polymer based on the total weight of the hydrocarbon fluid.

copolymer of up to bout 10 percent by weight of an acrylamide andisodecylmethacrylate.

7. An improved process for fracturing an earth formation penetrated by awell comprising injecting a hydrocarbon fracturing fluid down the wellinto the earth formation under pressure to cause fracturing of the earthformation wherein the improvement comprises treating the hydrocarbonfracturing fluid prior to injection with an aqueouspolyisodecylmethacrylate emulsion comprising (a) from 25 to 50 percentby weight polyisodecylmethacrylate, (b) from 15 to 40 percent by weightethylene glycol, (c) from 20 to 50 percent by weight water, and (d) from1 to 5 percent by weight surfactant, said polyisodecylmethacrylateemulsion being added in an amount such that the treated hydrocarbonfluid contains from about 200 ppm. to 500 ppm. ofpolyisodecylmethacrylate polymer based on the total weight of thehydrocarbon fluid.

8. The process of reducing frictional pressure loss in hydrocarbonfluids flowing through a conduit comprising adding to said hydrocarbonfluid an aqueous polymer emulsion comprising (a) from 20 to 60 percentby weight of a polymer of where R, is H or CH, and Rf is an alkyl groupof eight to 18 carbon atoms, (b) from 10 to 50 percent by weight glycol,(c) from 10 to 60 percent by weight water, and (d) from 1 to 10 percentby weight surfactant, said polymer emulsion being added in an amountsuch that the resulting hydrocarbon fluid contains from about 50 p.p.m.to 1,000 ppm. of active polymer based on the total weight of thehydrocarbon fluid.

9. A process as in claim 8 wherein the glycol is ethylene glycol.

10. A process as in claim 8 wherein R," is CH; and R is an isodecylgroup.

11. A process as in claim 8 wherein the polymer is a copolymer of up toabout 10 percent by weight of an acrylamide and isodecylmethacrylate.

12. A process as in claim 8 wherein the polymer is a copolymer of up toabout 10 percent by weight of dimethyl diallyl ammonium chloride andisodecylmethacrylate.

2. A process as in claim 1 wherein the glycol is ethylene glycol.
 3. Aprocess as in claim 1 wherein ''''R1'''' is CH3 and ''''R2'''' is anisodecyl group.
 4. A process as in claim 1 wherein the polymer is acopolymer of up to about 10 percent by weight of a dialkyl diallylammonium chloride and isodecylmethacrylate.
 5. A process as in claim 4wherein the dialkyl diallyl ammonium chloride is dimethyl diallylammonium chloride.
 6. A process as in claim 1 wherein the polymer is acopolymer of up to bout 10 percent by weight of an acrylamide andisodecylmethacrylate.
 7. An improved process for fracturing an earthformation penetrated by a well comprising injecting a hydrocarbonfracturing fluid down the well into the earth formation under pressureto cause fracturing of the earth formation wherein the improvementcomprises treating the hydrocarbon fracturing fluid prior to injectionwith an aqueous polyisodecylmethacrylate emulsion comprising (a) from 25to 50 percent by weight polyisodecylmethacrylate, (b) from 15 to 40percent by weight ethylene glycol, (c) from 20 to 50 percent by weightwater, and (d) from 1 to 5 percent by weight surfactant, saidpolyisodecylmethacrylate emulsion being added in an amount such that thetreated hydrocarbon fluid contains from about 200 p.p.m. to 500 p.p.m.of polyisodecylmethacrylate polymer based on the total weight of thehydrocarbon fluid.
 8. The process of reducing frictional pressure lossin hydrocarbon fluids flowing through a conduit comprising adding tosaid hydrocarbon fluid an aqueous polymer emulsion comprising (a) from20 to 60 percent by weight of a polymer of
 9. A process as in claim 8wherein the glycol is ethylene glycol.
 10. A process as in claim 8wherein ''''R1'''' is CH3 and ''''R2'''' is an isodecyl group.
 11. Aprocess as in claim 8 wherein the polymer is a copolymer of up to about10 percent by weight of an acrylamide and isodecylmethacrylate.
 12. Aprocess as in claim 8 wherein the polymer is a copolymer of up to about10 percent by weight of dimethyl diallyl ammonium chloride andisodecylmethacrylate.